Least-cost light-duty vehicle fleet decarbonization and the electric vehicle conundrum

This paper evaluates the greenhouse gas (GHG) emissions and financial performance of the U.S. light-duty vehicle (LDV) fleet. It develops dynamic models for conventional (ICEV), hybrid (HEV), plugin hybrid (PHEV) and battery electric (BEV) LDVs in four vehicle classes (compact, sedan, SUV and pickup truck), estimating their component sizes, purchase prices, embodied emissions, fuel consumption, life cycle GHG emissions and total cost of ownership (TCO) as a function of vehicle miles travelled (VMT). These dynamic models are applied to the US LDV fleet with its wide range of VMT per vehicle, revealing that ICEVs have the lowest TCO at lower VMT, but HEVs and BEVs become more cost-effective as VMT increases. Financially optimal powertrain choice can then reduce fleet-wide GHG emissions by one-third with current technologies, without any subsidies or increased costs. Technological advances, particularly in battery costs and electricity emissions, are then powerful drivers of further fleet decarbonization.